From Cppreference
|
|
|
|
|
|
|
template<
class CharT,
class Traits = std::char_traits<CharT>
> class basic_ofstream;
|
|
|
|
|
|
The class template basic_ofstream implements output operations on file based streams. It essentially wraps a raw file device implementation (basic_filebuf) into a higher-level interface (basic_ostream). The complete interface to unique basic_filebuf members is provided.
Two specializations for common character types are also defined:
| Defined in header <fstream>
|
|
|
| Type
| Definition
|
|
|
| ofstream
| basic_ofstream<char>
|
|
|
| wofstream
| basic_ofstream<wchar_t>
|
[edit] Member types
|
|
| Member type
| Definition
|
|
|
| char_type
| CharT
|
|
|
| traits_type
| Traits
|
|
|
| int_type
| Traits::int_type
|
|
|
| pos_type
| Traits::pos_type
|
|
|
| off_type
| Traits::off_type
|
[edit] Member functions
|
|
|
| constructs the file stream
(public member function)
|
|
|
|
| moves the file stream
(public member function)
|
|
|
|
| swaps two file streams
(public member function)
|
|
|
|
| returns the underlying raw file device object
(public member function)
|
File operations
|
|
|
|
| checks if the stream has an associated file
(public member function)
|
|
|
|
| opens a file and associates it with the stream
(public member function)
|
|
|
|
| closes the associated file
(public member function)
|
Member functions
Formatted input
|
|
|
|
| inserts formatted data
(public member function)
|
Unformatted input
|
|
|
|
| inserts a character
(public member function)
|
|
|
|
| inserts blocks of characters
(public member function)
|
Positioning
|
|
|
|
| returns the output position indicator
(public member function)
|
|
|
|
| sets the output position indicator
(public member function)
|
Miscellaneous
|
|
|
|
| synchronizes with the underlying storage device
(public member function)
|
Member classes
|
|
|
| implements basic logic for preparation of the stream for output operations
(public member class)
|
Member types
|
|
| Member type
| Definition
|
|
|
| char_type
| CharT
|
|
|
| traits_type
| Traits
|
|
|
| int_type
| Traits::int_type
|
|
|
| pos_type
| Traits::pos_type
|
|
|
| off_type
| Traits::off_type
|
State functions
|
|
|
|
| checks if no error has occurred i.e. I/O operations are available
(public member function)
|
|
|
|
| checks if end-of-file has been reached
(public member function)
|
|
|
|
| checks if a recoverable error has occurred
(public member function)
|
|
|
|
| checks if a non-recoverable error has occurred
(public member function)
|
|
|
|
| checks if an error has occurred (synonym of fail())
(public member function)
|
|
|
|
| checks if no error has occurred (synonym of good())
(public member function)
|
|
|
|
| returns state flags
(public member function)
|
|
|
|
| sets state flags
(public member function)
|
|
|
|
| clears error and eof flags
(public member function)
|
Formatting
|
|
|
|
| copies formatting information
(public member function)
|
|
|
|
| manages the fill character
(public member function)
|
Miscellaneous
|
|
|
|
| manages exception mask
(public member function)
|
|
|
|
| sets the locale
(public member function)
|
|
|
|
| manages associated stream buffer
(public member function)
|
|
|
|
| manages tied stream
(public member function)
|
|
|
|
| narrows characters
(public member function)
|
|
|
|
| widens characters
(public member function)
|
Member functions
Formatting
|
|
|
|
| manages format flags
(public member function)
|
|
|
|
| sets specific format flag
(public member function)
|
|
|
|
| clears specific format flag
(public member function)
|
|
|
|
| manages decimal precision of floating point operations
(public member function)
|
|
|
|
| manages field width
(public member function)
|
Locales
|
|
|
|
| sets locale
(public member function)
|
|
|
|
| returns current locale
(public member function)
|
Internal extensible array
|
|
|
|
| returns an unique index to be used to access elements in the internal extensible array
(public static member function)
|
|
|
|
| accesses specified element in the internal extensible array of long elements
(public member function)
|
|
|
|
| accesses specified element in the internal extensible array of void* elements
(public member function)
|
Miscellaneous
|
|
|
|
| registers event callback function
(public member function)
|
|
|
|
| sets whether C++ and C IO libraries are interoperable
(public static member function)
|
Member classes
|
|
|
|
| stream exception
(public member class)
|
|
|
|
| initializes standard stream objects
(public member class)
|
Member types and constants
|
|
|
| Type
| Explanation
|
|
|
|
| stream open mode type
The following constants are also defined:
|
|
| Constant
| Explanation
|
|
|
| app
| seek to the end of stream before each write
|
|
|
| binary
| open in binary mode
|
|
|
| in
| open for reading
|
|
|
| out
| open for writing
|
|
|
| trunc
| discard the contents of the stream when opening
|
|
|
| ate
| seek to the end of stream immediately after open
|
|
|
|
|
| formatting flags type
The following constants are also defined:
|
|
| Constant
| Explanation
|
|
|
| dec
| uses decimal base for conversions
|
|
|
| oct
| use octal base for conversions
|
|
|
| hex
| use hexadecimal base for conversions
|
|
|
| basefield
| dec|oct|hex. Useful for masking operations
|
|
|
| left
| left adjustment (adds fill characters to the right)
|
|
|
| right
| right adjustment (adds fill characters to the left)
|
|
|
| internal
| internal adjustment (adds fill characters to the internal designated point)
|
|
|
| adjustfield
| left|right|internal. Useful for masking operations
|
|
|
| scientific
| generate floating point types using scientific notation
|
|
|
| fixed
| generate floating point types using fixed notation
|
|
|
| floatfield
| scientific|fixed. Useful for masking operations
|
|
|
| boolalpha
| insert and extract bool type in alphanumeric format
|
|
|
| showbase
| generate a prefix indicating the numeric base for integer number output
|
|
|
| showpoint
| generate a decimal-point character unconditionally for floating-point number output
|
|
|
| showpos
| generate a + character for non-negative numeric output
|
|
|
| skipws
| skip leading whitespace before certain input operations
|
|
|
| unitbuf
| flush the output after each output operation
|
|
|
| uppercase
| replace certain lowercase letters with their uppercase
equivalents in certain output output operations
|
|
|
|
|
| state of the stream type
The following constants are also defined:
|
|
| Constant
| Explanation
|
|
|
| goodbit
| no error
|
|
|
| badbit
| irrecoverable stream error
|
|
|
| failbit
| input/output operation failed (formatting or extraction error)
|
|
|
| eofbit
| associated input sequence has reached end-of-file
|
|
|
|
|
| seeking direction type
The following constants are also defined:
|
|
| Constant
| Explanation
|
|
|
| beg
| the beginning of a stream
|
|
|
| end
| the ending of a stream
|
|
|
| cur
| the current position of stream position indicator
|
|
|
|
|
| specifies event type
|
|
|
|
| callback function type
|
